BackstagesDISCOVER OUR DEPOSITDiscover our product
Originating from a unique deposit in Europe and completely natural, PROMPT cement, exclusive to the Vicat Group, has been manufactured for over 180 years in the Chartreuse massif. Explore its deposit, exceptional properties, and manufacturing process that has remained unchanged since the 19th century.
Discover our deposit
A deposit located in France
In the heart of the Chartreuse massif, in the Isère department, an exceptional deposit is exploited for the production of PROMPT natural cement. This limestone massif is located in France, north of Grenoble, and is part of the subalpine chain. Its particularity lies in its folded and deformed sedimentary strata during the Alpine orogeny. This unique deposit consists of a geological layer composed of clayey limestone with a regular, precise, and homogeneous chemical and mineralogical composition. No external additives are used, unlike artificial cements, making it suitable for the production of natural cement.
Extraction of the Prompt stone: an underground deposit of clayey limestone with unique characteristics.
This layer of Prompt stone, inclined at 30° to 40°, is exploited using the room-and-pillar method in two underground quarries. The experienced miners have a perfect knowledge of the deposit, and their expertise allows them to visually follow this layer of stone. The extraction of the stone is fully mechanized and occurs in several phases:
- Drilling for blasting, preparation of blasting charges, and explosive blasting in horizontal galleries connected by a helical ramp
- Extraction of the stone
- Transport to shafts
- Finally, loading the stone into wagons for transportation outside
It should be noted that other operations are also necessary, such as securing the galleries with mesh and bolting for support, constructing a workshop in the quarry to maintain the equipment, and implementing a radio system to keep the personnel in contact.
After extraction, the stone is transported from the quarry to the La Pérelle cement plant, established in 1875 by Joseph Vicat. This cement plant is unique in the world as PROMPT natural cement is the only natural cement produced industrially.
A natural cement with unique properties
Because it comes from a natural deposit, PROMPT cement has a much lower ecological footprint compared to artificial cements. It is fired at a lower temperature than Portland cement (between 500°C and 1,200°C), resulting in significantly reduced pollutant emissions during this stage. These characteristics make it an environmentally responsible cement. Furthermore, the exceptional mineralogy of PROMPT natural cement provides it with unique properties such as fast setting and hardening. PROMPT natural cement allows for diverse applications: rapid masonry, restoration and decoration, eco-construction, and in the field of water and sanitation.
To learn more about our manufacturing process, also explore our grinding and firing methods.
In the hearth of Chartreuse